Exterior parts for a timepiece

ABSTRACT

Artifacts are prepared by reducing rocks, minerals, seashells and pigments to powders, distributing said powders in patterns, either mixed or unmixed, and binding said powders together as by sintering or the use of adhesives. Preferred artifacts are exterior components of watches.

United States Patent [191 Kasai et al.

[ Jan. 21, 1975 EXTERIOR PARTS FOR A TIMEPIECE [75] Inventors: Masami Kasai, Suwa;Toshio1mai,

Okaya, both of Japan [73] Assignee: Kabushiki Kaisha Suwa Seikosha,

Tokyo, Japan [22] Filed: Mar. 23, 1973 21 Appl. No.: 344,388

[30] Foreign Application Priority Data [56] References Cited UNITED STATES PATENTS 3,242,664 3/1966 Lederrey 553/88 R 3,669,695 6/1972 ller 58/88 R 3,690,062 9/1972 Kasai et a1. 58/88 R 3,726,082 4/1972 Kushida 58/88 G Primary ExaminerWilliam E. Schulz Attorney, Agent, or Firm-Blum Moscovitz Friedman & Kaplan [5 7 ABSTRACT Artifacts are prepared by reducing rocks, minerals, seashells and pigments to powders, distributing said powders in patterns, either mixed or unmixed, and binding said powders together as by sintering or the use of adhesives. Preferred artifacts are exterior components of watches.

7 Claims, No Drawings EXTERIOR PARTS FOR A TIMEPIECE BACKGROUND OF THE INVENTION A number of materials, both metallic and nonmetallic, are suitable for use independently in the manufacture of artifacts which may be subjected to corrosion and abrasion. Such materials may be either metallic or nonmetallic and include, as examples. plastics, stainless steel and ultra-hard alloys. Conditions are particularly severe where such materials are used in watchcase components, where they are subjected to corrosion and to abrasion. Those materials which do not have the necessary hardness and abrasion resistance or which are not attractive in appearance may undergo surface treatment such as corrosion-proofingas by electroplating, the alumite treatment and even coating with a paint. However, paint itself, while it may be attractive in appearance, is hardly abrasion resistant. Moreover, the range of materials, whether used independently or with surface treatment is relatively limited.

In the attempt to please the consumer, there is a continuing effort to develop designs which are fresh, new, attractive and, in addition, retain resistance to both corrosion and abrasion. The effort for fresh, new designs is particularly important where watchcases are concerned. Such cases continually are subjected to the corrosive effects of perspirationand frequently come in contact with abrasive materials such as concrete and cement.

SUMMARY OF THE INVENTION Hard rock, minerals, seashells and inorganic pigments are first reduced to fine powders and then arranged in patternsin which the various powders are either blended or unblended. The powders are then treated to make the particles adhere to each other. The treatment may consist of sintering, where the materials can be raised to a sintering temperature without destruction of the color, or bonding by the use of adhesives. The pattern may be arranged on the surface of a base metal to which it is bonded either by sintering or by the use of an adhesive, or the powders after bonding may be self-supporting if the item fabricated thereof is thick enough. Suitable artifacts for the use of such materials are watchcase components such as a dial, a bezel, an exterior case body, a coating on an exterior case body, indicia and items of costume jewelry.

Accordingly, an object of the present invention is the production of artifacts of improved appearance from minerals, rocks, inorganic pigments and seashells.

Another object of the present invention is the production of artifacts such as exterior watch components using minerals, rocks, seashells and inorganic pigments in powdered form.

An important object of the present invention is to provide artifacts which are decorative and which are formed of colored minerals, rocks, inorganic pigments and seashells in powdered form where the various powders are arranged in decorative and attractive fashion.

Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.

The invention accordingly comprises an article of manufacture possessing the features, properties, and the relation of elements which will be exemplified in the article hereinafter described, and the scope of the invention will be indicated in the claims.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Artifacts, and especially exterior components of 5 watch-cases, are made from powders derived from a variety of materials. The powders are bonded together either by use of an adhesive or by sintering. The powders may be applied to a base metal; if sintering is to be used the method of bonding of the powder to itself and to the base metal, then the base metal must have a higher melting point than the sintering temperature of the powder orpowders used. Alternatively, the powder or powders may be bonded to the base metal support by the use of a suitable adhesive. Where the powders are used in sufficient thickness, components free of any support may be formed. Again, the method of providing adherence between particles of powder is by sintering, where appropriate, or by the use of suitable adhesives.

Where rocks are to be used as the source of powders, the rocks may be eruptive, sedimentary or metamorphic in origin. Examples are sulfide minerals and sulfite minerals such as argentite, pyrite and cobalt glance; oxide minerals and hydroxide minerals such as cuprite, tenorite, hematite and spinel; halide minerals such as fluorite and cryolite; carbonate minerals such as dolomite, dialogite and malachite; sulfate minerals such as anhydrite and cyanosite; phosphate minerals and arsenate minerals such as xenotime, apatite and pyromorphite; tungstate minerals and molybdateminerals such as ferberite and cupro-scheelite;v silicic acid minerals such as quartz, ferruginous quartz and rock crystal; silicate minerals such as chrysolite, zircon, garnet, epidote, jadeite, calamite, manganese zeolite and diorite; nitrate minerals and borate minerals.

The rocks or minerals are reduced to powder by grinding, and if necessary, ball-milling, after which they may be mixed with a lubricant in order to facilitate compressing. They are then compressed and optionally presintered to prepare a preform. They are then sintered either by themselves or with a suitable binding material mixed into the powder.

Products made from such rock minerals have high mechanical strength and may be arranged into a variety of patterns, such as stripes, spots and designs of unlimited variety. Following is an example of the preparation of a product in accordance with the present invention: Diorite, also known as black granite, is pulverized mechanically and then mixed in a wet ball mill. The powder is dried and mixed with a small quantity oflubricant such as a paraffin wax to facilitate compacting in a press. Compacting is carried out in a die corresponding to the product which it is desired to make. As aforenoted, the process is particularly applicable for the manufacture of watchcase exterior components.

The pressure required for preparing a preform is about 2 tons/cm? Finally, sintering is carried out for a period of about an hour at a temperature of 1,350C.

The product of the above sequence of operations is finally polished in accordance with conventional processes, taking into account the hardness of the particular object. In the present case, the object can be polished to a high luster having a most attractive appearance. Moreover, the product is extremely hard, so that it is abrasion resistant and is corrosive resistant as well.

The hardness of an object prepared by sintering diorite is about 750-800 Hv on the Vickers hardness scale.

Surprisingly, the hardness of the sintered object is greater than that of diorite as found, the hardness of the latter being 500-600 Hv on the Vickers scale. Moreover, the forming process makes it possible to prepare objects in a much wider variety of shapes than would be the case with the stone itself. Also, considering its greater strength, complex shapes can be made by the powder process. As an example of the difference in strength between the two types of diorite, a drop test onto concrete was performed. Watchcases of the sintered product and of natural black granite (diorite) were dropped from a height of 1 meter. The case formed of natural black granite broke at a corner on the very first drop. On the second test, the piece shattered. In contrast, the case formed of sintered black granite according to the present invention withstood the drop test times, making it clear that products prepared in accordance with the present invention may actually be stronger than the natural product itself.

Asaforenoted, powders from a variety of colored rock minerals may be used together, either blended or unblended, to give a great variety of patterns. The variety can be further increased by combining such powders with inorganic pigments. Examples of such pigments are precipitated barium sulfate, alumina white, titanolith, zinc white, carbon black, chrome black, silicon carbide, slate powder, chromium tin red, umber, iron oxide, yellow lead, zinc chromate, chromium oxide green, cobalt, chrome green, Prussian blue, permane'nt blue, manganese purple, deep cobalt and metallic powder pigments.

Combining rock mineral powders with inorganic pigments results in an improvement in mechanical strength and density. Moreover, colors become available which have not hitherto been obtainable by conventional metalworking surface treatments. It should be noted that organic pigments are not practical because they are not resistant to mechanical abrasion, have poor chemical corrosion resistance and tend to fade when subjected to light. Moreover, they cannot be sintered.

Following is an example of the use of an inorganic pigment; Andalusite, one of the silicate materials used as a refractory or in special procelains, is roughly pulverized, mixed with powdered zirconium oxide and placed dry in a ball mill. After grinding to the required degree of fineness, a small quantity of lubricant such as paraffin is added to facilitate forming in a press. The composition is formed in a die in the shape of a bezel having an inside diameter of 30mm, using a pressure of 1.8 ton/em The preform is then sintered for one hour at the sintering temperature of l,200C.

The component, namely a bezel, produced in accordance with the above procedure is then polished in accordance with the usual techniques. The strength is I quite adequate for its projected usage, namely holding a glass in relation to a watehcase.

The andalusite by itself has a strong red color. In

combination with the zirconium oxide the color is lightened in proportion to the ratio of the materials used. Consequently, it becomes possible to achieve any shade of red between a deep red and white by suitable adjustment of the ratio of the components to each other.

As a means of producing desirable patterns, various combinations of andalusite and zirconium oxide, both blended and unblended, may be arranged in accordance with the desire of the designer to give most attractive effects. In addition, a bezel, for instance, made by such a technique has excellent light-resistance and heat-resistance, as well as corrosion-resistance. Moreover, it is not easily scratched, since its hardness is between 800 and 1,000 Hv on the Vickers scale. Consequently, such a component satisfies all of the requirements for an exterior component of a timepiece. Similarly, it is suitable for many types of artifacts and costume jewelry. It should be noted that if an attempt were made tofashion directly from the underground mineral a bezel or an other component subjected to substantial mechanical stress, the product would not be nearly so satisfactory as is that made by the process of the present invention.

In addition to colored rock minerals and inorganic pigments, artifacts and watch components similar to those described above may also be made from seashells using somewhat similar techniques. Many types of shellfish have brilliantly colored shells. in some cases the shells are permeated with the color, so that the shell has essentially the same color throughout, and in other cases the surface color is different from the interior color.

Such shells are readily pulverized to a fine powder and can be used to produce brilliantly colored artifacts, and especially watehcase components. Where the composition of a specific shell and the powder derived therefrom are suitable, the powder may be sintered. Otherwise, bonding is accomplished by the use of an adhesive.

Suitable shells are those from shellfish belonging to class polyplacophora, such as subclass paleoloricate, and order lepidopleurida; class gastropoda, such as order archaeogastropoda, and order mesogastropoda; class pelecypoda, such as order dysodonta, and order anomalodesmata; class cephalopoda, such as subclass tetrabranchia and order nautiloidea; and other class scaphopoda and class monoplacophora.

Shells are particularly valuable because of the fact that they provide iridescence. Although they can be blended with any of the colored rock minerals or inorganic pigments, if it is desired to use shell-powder in combination with such materials, it is preferable that they be used side by side rather than mixed. Otherwise, such iridescence as may be present is lost or diluted. Following is an example of the procedure used.

The shell of perriere, a red shellfish, has the advantage that the shell is red both on the exterior and the interior thereof. It is roughtly pulverized mechanically an then ballmilled dry. A small quantity of lubricant such as paraffin is added to aid in press-forming. It is compacted in a die having the shape of an indicium to be placed on a watch dial, the indicium measuring 4 X l X lmm. The pressure used is 1.5 ton/cm The material is then sintered for 45 minutes at a sintering temperature of 350C.

After polishing by conventional processes, the indicium is placed on a dial and cemented thereto. An indicium of the specific material named is brilliant and appears to glow from within in a manner similar to that of a ruby or an opal, so that the ornamental effect is quite striking. The effect is, of course, quite different from that obtained with a plated metal and is generally considered far superior in attractiveness. Moreover,

whereas the shape of a piece which can be cut from natural shell is quite limited due to the limitation in dimension and thickness of the shell itself, by the use of the powdering process, followed by pressing and sintering, it becomes possible to make indicia as well as hands and other components which vary greatly in shape and color. Moreover, it is extremely difficult to produce the iridescent effect yielded by artifacts molded from powdered shells and appropriately bonded. As is apparent, self-supporting components can be made in this fashion, or components which are relatively thin can be applied as a coating to base metals or other substrates. Furthermore, it is possible to use the powderedshell material in combination with minerals which require a far higher sintering temperature. For this purpose, an artifact in which it is planned to use both mineral powder and shell powder can be made generally as follows:

Assume that the powders are to be applied to a base metal. Sections to be made of mineral powder are formed by compressing and sintering at the required high temperature, and sections to be made of shell powder are formed and sintered at the relatively low temperature. The parts are then cemented onto the base metal in the form of a mosaic.

Where no base metal is to be used, the basic structure can be formed of the rock mineral powder, leaving gaps to be filled in later with shell powder. The basic structure is formed of the powder and sintered. The shell powder sections are likewise formed and sintered, but of course at a lower temperature. The shell powder components are then cemented into place in the complete structure.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the above article without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

What is claimed is:

1. A decorative matrix comprising sintered fines of a naturally occurring rock material, said matrix being characterized by a hardness which exceeds that of an integral fragment of said naturally occurring rock material.

2. The decorative matrix as claimed in claim I wherein said fines of said naturally occurring rock material is selected from the group consisting of argentite. pyrite, cobalt glance, cuprite. tenorite. hematite. spinel, fluorite, cryolite, dolomite, dialogite. malachite. anhydrite, cyanosite, xenotime, apatite, pyromorphite, ferberite, cupro-scheelite, quartz, ferruginous quartz, rock crystal, chrysolite, zircon, garnet, epidote, jadeite. calamite, manganese zeolite, and diorite.

3. The decorative matrix as claimed in claim 1 including an inorganic pigment randomly dispersed therein.

4. The decorative matrix as claimed in claim 3 wherein said pigment is selected from the group consisting of precipitated barium sulfate, alumina white. zinc white, chrome black, silicon carbide, slate powder, rouge, chromium tin red, yellow lead, zinc chromate, chromium oxide green, cobalt, chrome green, Prussian blue, permanent blue and metallic powder pigments.

5. The decorative matrix as claimed in claim 1 including a specific distribution of shell fines therein.

6. The decorative matrix as claimed in claim 1 wherein said sintered fines are diorite and said matrix is characterized by a Vickers hardness of about 750 to about 800 Hv.

7. The decorative matrix as claimed in claim 3 wherein said sintered fines are andalusite and said inorganic pigment is zirconium oxide, said matrix being characterized by a Vickers hardness of about 800 to about 1,000 Hv. 

2. The decorative matrix as claimed in claim 1 wherein said fines of said naturally occurring rock material is selected from the group consisting of argentite, pyrite, cobalt glance, cuprite, tenorite, hematite, spinel, fluorite, cryolite, dolomite, dialogite, malachite, anhydrite, cyanosite, xenotime, apatite, pyromorphite, ferberite, cupro-scheelite, quartz, ferruginous quartz, rock crystal, chrysolite, zircon, garnet, epidote, jadeite, calamite, manganese zeolite, and diorite.
 3. The decorative matrix as claimed in claim 1 including an inorganic pigment randomly dispersed therein.
 4. The decorative matrix as claimed in claim 3 wherein said pigment is selected from the group consisting of precipitated barium sulfate, alumina white, zinc white, chrome black, silicon carbide, slate powder, rouge, chromium tin red, yellow lead, zinc chromate, chromium oxide green, cobalt, chrome green, Prussian blue, permanent blue and metallic powder pigments.
 5. The decorative matrix as claimed in claim 1 including a specific distribution of shell fines therein.
 6. The decorative matrix as claimed in claim 1 wherein said sintered fines are diorite and said matrix is characterized by a Vickers hardness of about 750 to about 800 Hv.
 7. The decorative matrix as claimed in claim 3 wherein said sintered fines are andalusite and said inorganic pigment is zirconium oxide, said matrix being characterized by a Vickers hardness of about 800 to about 1,000 Hv. 